Once a neural circuit network is damaged by brain injury or spinal cord injury and the network is thereby cut off or results in nerve cell death, the physiological and/or motor functions governed by nerves are lost, and it becomes extremely difficult to restore the neural circuit. Neurites are often packed with microtubule bundles, the growth of which is stimulated by Nerve Growth Factor (NGF), as well as tau proteins, MAP1, and MAP2. U.S. Pat. No. 6,207,639 provides methods for enhancing and/or directing neurite outgrowth, comprising contacting a neuron with a cell adhesion modulating agent, wherein the modulating agent enhances cadherin-mediated cell adhesion. U.S. Pat. No. 7,846,438 discloses contacting a neuron (such as a CNS neuron) with an effective amount of an agent that modulates TAJ complex formation and/or signaling to modulate growth and/or survival of a neuron. U.S. Pat. No. 8,481,711 provides a non-peptidic nerve axon and/or neurite outgrowth agent for allowing a nerve axon and a neurite to elongate.
Many therapeutic effects have been reported of Lingzhi species, such as immunomodulatory, anti-tumor, hepato-protective, antioxidant, and cholesterol-lowering effects (Jinn et al., 2006, Biosci Biotechnol Biochem, 70, 2627-2634). All of these therapeutic effects are attributed to triterpenoids, polysaccharides, and glycoproteins (Boh et al., 2007, Biotechnol Annu Rev, 13, 265-301; Jinn et al., 2006, Biosci Biotechnol Biochem, 70, 2627-2634). A new glycoprotein class in Lingzhi named fungal immunomodulatory proteins (FIPs) was recently identified. So far, at least 4 FIPs have been isolated and purified from Ganoderma lucidum, LZ-8, (G. lucidum), FIP-gts (Ganoderma tsugae), and FIP-gja (Ganoderma sinensis) (Hsu et al., 1997, Biochem J, 323 (Pt 2), 557-565; Ko et al., 1995, Eur J Biochem, 228, 244-249; Xuanwei et al., 2008, Planta Med, 74, 197-200). According to a previous study, FIP-gts from G. tsugae, a popular chemopreventive mushroom in Asia, has anti-cancer function and is involved in the regulation of hTERT/telomerase expression (Liao et al., 2006, Mol Carcinog, 45, 220-229). In addition, FIP-gts inhibits the growth of A549 cancer cells, leading to cell cycle arrest, consequently inducing premature cellular senescence in lung cancer cells. Moreover, FIP-gts results in significant inhibition of tumor growth in athymic nude mice implanted with A549 cells (Liao et al., 2008, Food Chem Toxicol, 46, 1851-1859). US 20100009915 provides a method for suppressing proliferation of a cancer cell and a method for suppressing a tumor cell mobility, comprising providing to the tumor cell a purified polypeptide of a fungal immunomodulatory protein, LZ-8. U.S. Pat. No. 7,601,808 discloses an immunomodulatory protein cloned from Ganoderma microsporum and this protein has immunomodulator efficiency.
However, no prior art discloses, teaches or suggests that immunomodulatory proteins from Ganoderma are relevant to neurite outgrowth.